Override user's style choice always

I would like to override my user's styling choice 100% of the time for my site. What's the easiest method to achieve this result?

I was looking at going page by page, which I can do, but it seems there has to be an easier way. Going to 30+ pages, and add-ons, and always having to follow up when other admins create a page, etc. seems there are too many opportunities for a miss.